Clutch



June 9; 1925'. 1,541,411

' l.. C. DAVIS CLUTCH Filed Aug. 12. 1922 IN VEN TOR.

@ATRE Y.

'Patented Jene 9,1925.

' UNITEDSTA TES PATENT OFFICE- LATTA o. DAv'Is, or INDIANAI'oLIs,INDIANA, AssIoNo'n' To WILLIAM M.. FoGARTY, TRUSTEE, o I INDIANAPOLIS,INDIANA. l

`Application ledvAugust 12,1922. Serial 11a-581,301.

y. lTo whom t'may camera:

Be itlknownthat I, LATTA O. DAVIS, .a citizen.y of the United Statesresiding at Indianapolis, in the countyv of Marion and State ofIndianahave invented a new and useful Clutch, of which...the followingis a specification.

It 'isfthe object of my invention to proc duce a clutch, especially anautomobile v clutch, in which there is'a balanced cushioning springbetween the ywheel l and the clutch; in which the friction ring of theclutch is removable and replaceable through an opening in the rim of theliywheel without requiring the entire dismantling of the clutch, so thatin consequence'ia worn-out friction ring may be replaced'in much lesstime than has heretofore been necessary; in which the setting andreleasing'mechanism 4of the clutch,"including the setting spring, is aunit which can be puton and removed from the shaft as a unit, butrequires no fastening` to the shaft otherwise than a bearing against ashoulder thereon; and in which a simple emergency locking device isprovided between one clutch member and the flywheel in the event of thebreakage or other disabling of the cushioning spring.

The accompanying drawing illustrates my invention: Fig. 1 is alongitudinal section through a `clutch embodying my invention; Fig. 2 isa transverse section on the line 2--2 of Fig. 1, to show the balancedsprin and Fig 3 is a fragmentary section on t e'lme 3-3 of Fig. 1, toshow the removable segment of a fly-wheel rim and the sectionalconstruction of the friction ring, and also to show the locking means'between one clutch member and the flywheel.

The iiywheel 10 may be in general of the usual type, with a rim 11, andis carried in any suitable way on the rear endy of the 'crank-shaft 12of the automobile engine.

Within the rim 11 is a clutch com osed of tened to the inner face oftheywheel 10,v

as by screws 20. The hub 17 canturn on the flange 18, but is heldagainstlongitudi` nal movement thereon by a anged clampino' plug 21 screwedinto the projecting end ofs the flange 18 so that its flange bears\against the clutch member 13. The clutchshaft 16 preferably extendsthrough the clamping plug 21, the hub 17 ,and the iiange 18, so thatvits end may be supported in a lligll-bearing 22 at the center oftheflywheel The hubj17 is connected tothe iiywheel rim llby a pair ofspiral springs 25. These two spira-l springs are similar, andareintercoiled with each other but with their corresponding ends spaced 180apart. vThe inner-ends of the spiral springs 25 have inturned fingers 26which are received in diametrically opposite notches in the outer faceof the hub 17., The outer ends of the springs 25 have out-turned hookedfingers 27 which project through diametricall'y o posite holes in theiywheel rim 11. Te

ceiling of the springs 25 is such that as the crank-shaft 12 is turnedby the engine it y the greatest spacing between turns is toward e theinside`ef the coil, as is clear from Fig. 2. As the springs are wound up4by the torque between the crank-,shaft 12 and the clutch-shaft 16, theycoil tightly about the hub 17, so that the spacing betweenA turns of thecoils travels outward toward the iiywheel rim. The first turn at ,theinside end of each coil at all times passes closely against theinturned" finger 26 of the other coil, so that each coil holds the iiner 26 of its companion in place in its not in the hub 17, and does. somore tightly as the springs are stressed. I prefer to providecrescent-shaped lugs 28 between the inmost two clutch members 13 and 14an Ya fricv radially outward adjacentpart of the ,other coil,4 toprevent undue bending of either spring over the nger 26 of its companionspring. This avoids any point of undue bending on tle. spring.Preferably the in ner surface of each lug 28 at that end 29 which isfarther from the shaft axis is, rounded olf to avoid 'a point of unduebending of the spring in case of -reverse powertransmission; as when thecar is coasting loo .les

; because they are free from unbalanced distorting stresses.

The friction ring 15 of the clutch is made in sections, as is clear fromFig. 3. Each section is in the shape of a sector, of the ring,conveniently of about one-sixth or oneeighth the circumference, thoughthe angular extent of the sectors is immaterial, Each sector, in thepreferred form shown, comprises a central Vmetal plate 30, with a facingY31 of friction material on each side. TheY flywheel rim is providedwith a removable sector 32 in the Vplane of the friction ring 15. lThissector 32 is preferably of VYslightly greater angular extent than is asector of the friction ring,'as is clear from Fig. 3; and is removablyheld in its place in the flywheel rim ll'in any suitable manner, as byradial screws 33Ylocated half in the sector 32 and half in thel body ofthe rim 11. By removing'the screws 33, the

rim sector 32 is loosened and may be removed; leaving 'an opening whichmay be brought to the bottoni of-the flywheel to let the segments of thefriction ring dropY out one at a time, by relative rotation of the ringand flywheel, and which may be brought to the top of the yflywheel topermit the-dropping in of the segments of the friction'wheel one at a'time. The segments are held from going too far-in by annular flanges 34on: the adjacent faces of the clutch members 13 and 14. After the seg;ments of the friction ring are put in place, the sector 32 is put backin place and fastened there by the screws 33. This makes it possible torepair or replace the friction ring when it is worn, without dismantlingthe entire clutch, and thus reduces the labor bill for repair-to' asmall fraction of what it would otherwise be.

The relative movement between the clutch members 13 and 14 as requiredfor setting and releasing the clutch may be obtained in any suitablemanner, but I prefer to use the arrangement illustrated in Fig. 1. lnsuch arrangement, the clutch member 14 is provided with a circularseries of attaching forks 35, conveniently screwed into such clutchmember; and these forks are pivoted to intermediate points on a similarcircular series of radial levers 36. There may be any desired number offorks 35 and levers 36,

.from two up. The inner ends of the levers 36 are pivoted to a collar 37which bears against a shoulder 38 on the clutch-shaft 16 and needs noother fastening. VYA coiled conical spring 39 co-aXial-with the clutchshaft 16 bears against the levers -'36 near their outer ends,conveniently through an interposed ring 39 to equalize the effect on theseveral levers, and acts between such levers and the flange.40 of ascrew plug 41 screwed within a rearwardly extending tubular flange 42from the collar 37. Thus the spring 39 really acts between the levers 36and the.V collar 37, and by its expansion keeps the collar 37 seatedagainst the shoulder 38. The outer ends of the levers 36 are connectedby links 43 to a clutch-actuating sleeve 44 slidable on the clutch-shaft16 and suitably operated by the fork 45 of the usual clutch-pedal,conveniently with a thrust bearing 46 interposed between the fork 45 anda suitable flange 47 on such clutch-actuatingcollar. When the clutchpedal is depressed, the outer-'ends of the levers 36 are drawn rearward,to compress the spring 39 and to release the friction ring of theclutch, thusreleasing the clutch. When the clutch pedal is allowed torise, the resultant expansion of the spring 39 forces the outer ends Yofthe levers 36 forward to move the clutch members 13 and 14 together tongrip the friction ring 15 andthus set the clutch. The wholeclutch-actu'- ating mechanism may be assembled on the clutch member 14,and slid on the clutchshaft Y16 as a unit, the clutch member 14 ofcourse on its spline, and no fastening is required other than thereaction of the parts.

Ine-order to provide for emergencies, in case the springs 25 break, lpreferably provide some means for interconnecting the clutch member 13directly to the flywheel 10 independently of the springs 25. `Whilc thismay be done in various ways, a convenient' way isto provide in theflywheel rim 11 one or more threaded holes 5() (scc Fig. 3), which mayreceive screws 51 which when screwed in will project inward bcyond theflywheel rim into holes or notches 52 provided in the outer edge of theclutch member 13. There may be any desired number of these holes 50 and52, all of course in the plane of the clutch member 13.

I claim as my invention:

1. 'In combination, a flywheel having a rim projecting axially to form ahousing, a clutch located withinsaid housing and having relativelymovable clutch members which by such relative movement set and releasethe clutchone of said clutch members having an axially projecting hub, aring carried by said flywheel and providing 'a bearing for said hub, anda spiral spring between said hub and the rimof thel flywheel.

2; In combination, a flywheel having a rim projecting axially to form ahousing, a clutch located within said housing and having relativelymovable clutch members y ring carried by said flywheel and providing abearingvfor 's'aid hub, and aV plurality ofv intercoiled spiral springsinterconnecting said hub and the' rimof the flywheel.

4. In combination, a flywheel having a rim projecting axially to form avhousing, a clutch located within. said housing and having relativelymovable clutch members which by such relativemovement set and releasethe clutchone of said clutch members having an axially projectinghub,and a plurality of interco-iled spiral springs inter-connecting said huband the rim of the flywheel.

5. In combination, a fl wheel having a rim projecting axially to orm ahousing, a

clutch located within said housing and having relatively movable vclutchmembers which 'bv .such relative movementl set and release the clutch,one of said clutch members having an axially projecting hub, and aplurality of intercoiled spiral springs interconnecting said hub and therim of the flywheel, the connections of said spiral springs to saidflywheel rim and to said hub respectively being substantially equallyspaced around the circumference thereof.

6. In combination, a flywheel having a rim projecting axially vto form ahousing, a. clutch located within said housing and having relativelymovableclutch members which b such relative movement set and release t eclutch, one of said clutch members having an. axially projecting hub,and a plurality of intercoiled spiral s rings interconnecting said huband the run ofthe flywheel, said spiral lsprings at their inner endsbeing provided with inwardly turned fi ers which project into notches insaid hu and each spring being arranged to bear on its neighboring springover such inturned finger to hold the latter in place. 7. Incombination, a flywheel havi a rim projecting axially to form a housing,a clutch located within said housingu and having relatively movableclutch members which 'b such relative movement set and, release t eclutch', one of said clutch members` having an axially projecting. hub,a

' plurality of intercoiled spiral springs interconnecting said hub andthe rim of the flywheel and crescent-shaped lugs carried by said tabbedclutch member forv guiding the coiling of said springs near their innerends. 4

8. In combination, a flywheel having a rim project-ing axially to form ahousing, a clutch located within said housing and having relativelymovable' clutch members which by such relative movement set and releasethe clutch, one of said clutch members having an axially projecting hub,and a spiral spring between said hub and the rim of the flywheel, saidsp-ring normally having its turns spaced farther apart toward ,the innerend than at the outer end so that as the spring is wound there is spacefor coiling around the inner end.

A9. In combination, aY flywheel having a rim projecting axially to forma housing, a clutch located within said housing and 'having relativelymovable clutch members which 'by such relative movement set and releasethe clutch, one of said clutch members havingan axially projecting hub,and a plurality of intercoiledspiral s rings interconnecting said huband therim of the flywheel, said springs normally having their turnsspaced farther apart toward 'the inner ends lthan at their outer ends sothat as the .springs are wound there is space for coiling around theinner ends.

10; In combination, a shaft, a clutch having relatively movableymembers,A one -of which is slidable on said shaft, a collar on saidshaft, said shaft lhaving a shoulder against which said collar abuts,levers pivvided with Ymeans for, limiting their relaj tive axialmovement, leverspivoted to said collar and projecting outward therefrom,

ysaid levers being connected at intermediate points tosaid clutch memberwhich is yslid:-

lable on said shaft, a spring acting'b'et/ween said collar and points onsaid levers farther outward thereon than the points of'connection tosaid clutch member, and means for swinging said levers to compress saidspring.

`12. In combination, a shaft, a clutch hav- I ing relatively movablemembers one of which is slidable on said shaft, a collar on said shaft,said shaft having a shoul- 59 levers being connected at intermediatepoints der lagainst which said collar abuts, levers pivoted to saidcollar and pro- 'ecting outward therefrom, said levers being connectedat intermediate points to said clutch member which is slidable on saidshaft, a spring acting between said collar and points on said leversfarther outward thereon than the ints of connection to said clutch lmemva sliding clutch-actuating sleeve, and means connecting said sleeve tothe outer ends of said levers.

13. In combination, a shaft, a clutch having relatively movablemembersone of which -is slida'ble on said shaft, a collar on said shaft, saidshaft and collar being provided with means for limiting their relativeaxial movement, levers pivoted to said eollar and projecting outwardtherefrom, said levers bei e, connected at intermediate points to saidclutch member which is slidafble on said shaft, a spring acting between`said collar and points on said levers farther outward thereenA than the.points of connection to said clutch member, a sllding clutchactuatingsleeve, and means connecting sald sleeve to the outer ends of saidlevers.

14. In combination, a shaft, a clutch hav- Ving relatively movablemembers one `of which is slidable' on said shaft, a collar on saidShaft, said shaft ,having a shoulder" against which said collar abuts,levers pivoted to said collar and rojecting outward therefrom, saidlevers eing connected at intermediate points to said clutch member whichis slidable on said shaft, a spring acting between said collar andpoints on said levers farther outward thereon than. the

points of l,connection to said clutch member, a ring interposed betweensaid spring and said. levers, and means for swinging said levers tocompress said spring.

`15. In combination, a shaft, a clutch having relatively movable membersone of which is slidable on said shaft, a collar on" said shaft, saidshaft and collar being provided with/means for limiting their relativeaxial movement, levers pivoted to said collar and projecting outwardtherefrom, said to said clutch member which is slidable on said shaft, aspring acting between said collar and points on said levers fartherout-- clutch members which bysuch axial movement may be clutchedtogether orde- `c1utched, said flywheel and one of said clutch membershaving interassociated bearing parts which hold them co-axial, and apair of intercoiled spiral springs between one of said clutch membersand said flywheel. v

17. In combination, a flywheel, a friction clutch having relativelyaxially movable clutch members which by such axial movement may beclutched together or declutched, one of said .clutch members havin ahub, a part carried by said flywheel and upon which said hub fits forholding such clutch member/and flywheel co-axial, and a pair ofintercoiled spiral springs connected at their inner endsto said huband-at their outer ends to said flywheel.

18. 'In combination, a ilywheel, a friction clutch co-axial with saidflywheel and having a plurality of clutch members which can be clutchedtogether and de-clutched,

said flywheel being provided with an an- `member of said clutch.

19. In combination, a ilywheel, a friction clutch co-axial with saidlywheeland having a plurality of clutch members which can be clutchedtogether vand -de-clutched, said flywheel being provided with an annularsupportin surface on which one of said clutch mem rs has a bearing, andthe clutchI and flywheel being spaced apart to provide a transverseannular space, and a spiral spring located in said annular space andinterconnecting said flywheel and a member of said clutch, the part towhich the outer end of said spiral spring is connected being providedwith a rim-flange which overlies said spring and forms a housing whichlimits the expansion of said spring.

20. Incombination, a flywheel, a friction `clutch co-axial with saidflywheel and having a plurality of clutch members which can be clutchedtogether and de-clutched, said flywheel being -provided with an annularsupporting surface on which one of said clutch members has a bearing,and the clutch and flywheel being spaced apart to provide a transverseannular space, and a spira-l spring located in said lannular space andhaving its outer end connected to said flywheel and its inner endconnected to the clutch member which has a/bearing on the flywheel.

21. In combinatiomja fi wheel, a friction clutch co-axial with saidy'wheel, and'having a plurality of'clutch members whichcan be clutchedtogether and de-clutched, said ilywheel being provided with an annularsupporting-surface on which one of said clutch members has a bearin andthe clutch andflywheelbeing spacedg apart to leo provide a transverseannular space, and a spiral spring located in said annular space andhaving its outer end connected to said flywheel and its inner endconnected to the clutch'meniberwliich has a bearing on the flywheel,said iywheel being provided with a flange which overlies the peripheryof said spiral spring and forms a housing which limits the expansion ofsuch spring.

22. In combination, two relatively rotatable parts, a friction clutchbetween said two parts for interconnecting them, and a plurality ofintercoiled springs interposed between said clutch and onevof said partswhich said clutch interconnects, each such spring normally having itsturns spaced farther apart toward the inner end than at the outer end sothat as the spring is wound there is space for `coiling around the-inner end.

23. In combination, two relatively rotatable parts, .a friction clutchbetween said two parts for interconnecting them, and a spring'interposed between said clutch and one of said parts which said clutchinterconnects, such spring normally having its turns spaced fartherapart toward ythe inner end than at the outer end so that as the springis wound there is space for coiling around the inner end, such widerspacingof spring? turns extending for at least one complete turn fromthe inner end of the spring.

' 24. In combination, two relatively rotatable parts, a friction clutch'between said two parts for interconnectingv them, a plurality ofintercoiled springs interposed between said clutch and one of said partswhich said clutch interconnects, and guiding means carried'by the memberto which the inner ends of said springs are connected and located4between spring-turns for guiding the coiling of said springs near theirinner ends.

- 25. In combination, two relatively rotatable parts, a friction clutchbetween said two parts for interconnecting them, a spring interposedbetween said clutch and one of Vsaid parts which said clutchinterconnects,- 'and' guiding means carried by the member to which theinner end of said spring is j lhundred and twenty-two.

ble parts, a friction clutch between said two l parts forinterconnecting them, av spring interposed between said clutchand one ofsaid parts which said clutch interconnects, and spacing means forproducing between adjacent spring-turns a crescent-shaped space.

28. In combination, two relatively rotatable parts, a friction clutchbetween said two parts for interconnecting them, a pair qf inter-coiledsprings interposed between said clutch and one of said parts which saidclutch interconnects, and spacing means for producing between adjacentspring-turns a space which is wide intermediately of the ends of thespace 'and gradually becomes narrower at the two ends of the space topermit such adjacent spring-turns to approach gradually into contactwithout a sharp bending point.

29. In combination, two relatively rotataf,

ble parts, a friction clutch between said two parts for interconnectingthem, a spring interposedbetween said clutch and one of said parts whichsaid clutch interconnects, and spacing means for producing betweenadjacent spring-turns a space which is wide intermediately of the endsof the space and gradually becomes narrower at the two ends of the spaceto permit such adjacent springturns to approach adually into contactwithout a sharp ben in' point. l

In witness whereof, have hereunto set my hand at Indianajglis, Indiana,this 9th day of August, A. one thousand nine LATTA o. Davis.

